How to create my own "Work-Out" without computer

Hi all, (sorry for my english 'cause i’m not).
Recently, it seems that the zwift’s version has been upgraded and my system’s computer doesn’t fit anymore. I can’t even open zwift on my mac.
Hopefully i had the apple tv where i can train on zwift but it appears that i can’t create and set up my own Work-Out on in.
Can someone tell me how to do it please ?
I only play Zwift for Work-out :confused:

Thank’s !